diff --git a/packages/cli/src/ui/hooks/useToolScheduler.test.ts b/packages/cli/src/ui/hooks/useToolScheduler.test.ts
index b2071931..8e060ee8 100644
--- a/packages/cli/src/ui/hooks/useToolScheduler.test.ts
+++ b/packages/cli/src/ui/hooks/useToolScheduler.test.ts
@@ -55,6 +55,11 @@ const mockConfig = {
   getApprovalMode: vi.fn(() => ApprovalMode.DEFAULT),
   getUsageStatisticsEnabled: () => true,
   getDebugMode: () => false,
+  getSessionId: () => 'test-session-id',
+  getContentGeneratorConfig: () => ({
+    model: 'test-model',
+    authType: 'oauth-personal',
+  }),
 };
 
 class MockToolInvocation extends BaseToolInvocation<object, ToolResult> {
diff --git a/packages/core/src/core/coreToolScheduler.test.ts b/packages/core/src/core/coreToolScheduler.test.ts
index 5cf49350..e0d7f65a 100644
--- a/packages/core/src/core/coreToolScheduler.test.ts
+++ b/packages/core/src/core/coreToolScheduler.test.ts
@@ -53,6 +53,10 @@ describe('CoreToolScheduler', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.DEFAULT,
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
@@ -109,6 +113,10 @@ describe('CoreToolScheduler with payload', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.DEFAULT,
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
@@ -405,6 +413,10 @@ describe('CoreToolScheduler edit cancellation', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.DEFAULT,
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
@@ -493,6 +505,10 @@ describe('CoreToolScheduler YOLO mode', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.YOLO,
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
@@ -578,6 +594,10 @@ describe('CoreToolScheduler request queueing', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.YOLO, // Use YOLO to avoid confirmation prompts
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
@@ -687,6 +707,10 @@ describe('CoreToolScheduler request queueing', () => {
       getUsageStatisticsEnabled: () => true,
       getDebugMode: () => false,
       getApprovalMode: () => ApprovalMode.YOLO,
+      getContentGeneratorConfig: () => ({
+        model: 'test-model',
+        authType: 'oauth-personal',
+      }),
     } as unknown as Config;
 
     const scheduler = new CoreToolScheduler({
diff --git a/packages/core/src/core/nonInteractiveToolExecutor.test.ts b/packages/core/src/core/nonInteractiveToolExecutor.test.ts
index 484d2e45..0c1164ea 100644
--- a/packages/core/src/core/nonInteractiveToolExecutor.test.ts
+++ b/packages/core/src/core/nonInteractiveToolExecutor.test.ts
@@ -20,6 +20,10 @@ const mockConfig = {
   getSessionId: () => 'test-session-id',
   getUsageStatisticsEnabled: () => true,
   getDebugMode: () => false,
+  getContentGeneratorConfig: () => ({
+    model: 'test-model',
+    authType: 'oauth-personal',
+  }),
 } as unknown as Config;
 
 describe('executeToolCall', () => {
diff --git a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.test.ts b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.test.ts
index 39596616..2777f196 100644
--- a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.test.ts
+++ b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.test.ts
@@ -181,12 +181,25 @@ describe('ClearcutLogger', () => {
 
       const event = logger?.createLogEvent(EventNames.API_ERROR, []);
 
-      expect(event?.event_metadata[0][0]).toEqual({
+      expect(event?.event_metadata[0]).toContainEqual({
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_GOOGLE_ACCOUNTS_COUNT,
         value: '9001',
       });
     });
 
+    it('logs the current surface from a github action', () => {
+      const { logger } = setup({});
+
+      vi.stubEnv('GITHUB_SHA', '8675309');
+
+      const event = logger?.createLogEvent(EventNames.CHAT_COMPRESSION, []);
+
+      expect(event?.event_metadata[0]).toContainEqual({
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SURFACE,
+        value: 'GitHub',
+      });
+    });
+
     it('logs the current surface', () => {
       const { logger } = setup({});
 
@@ -195,7 +208,7 @@ describe('ClearcutLogger', () => {
 
       const event = logger?.createLogEvent(EventNames.API_ERROR, []);
 
-      expect(event?.event_metadata[0][1]).toEqual({
+      expect(event?.event_metadata[0]).toContainEqual({
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_SURFACE,
         value: 'ide-1234',
       });
@@ -238,7 +251,7 @@ describe('ClearcutLogger', () => {
         expectedValue: 'cloudshell',
       },
     ])(
-      'logs the current surface for as $expectedValue, preempting vscode detection',
+      'logs the current surface as $expectedValue, preempting vscode detection',
       ({ env, expectedValue }) => {
         const { logger } = setup({});
         for (const [key, value] of Object.entries(env)) {
@@ -246,7 +259,7 @@ describe('ClearcutLogger', () => {
         }
         vi.stubEnv('TERM_PROGRAM', 'vscode');
         const event = logger?.createLogEvent(EventNames.API_ERROR, []);
-        expect(event?.event_metadata[0][1]).toEqual({
+        expect(event?.event_metadata[0][3]).toEqual({
           gemini_cli_key: EventMetadataKey.GEMINI_CLI_SURFACE,
           value: expectedValue,
         });
diff --git a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
index 7777fa24..7369bc1b 100644
--- a/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
+++ b/packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts
@@ -7,13 +7,11 @@
 import { HttpsProxyAgent } from 'https-proxy-agent';
 import {
   StartSessionEvent,
-  EndSessionEvent,
   UserPromptEvent,
   ToolCallEvent,
   ApiRequestEvent,
   ApiResponseEvent,
   ApiErrorEvent,
-  FlashFallbackEvent,
   LoopDetectedEvent,
   NextSpeakerCheckEvent,
   SlashCommandEvent,
@@ -129,6 +127,8 @@ const MAX_RETRY_EVENTS = 100;
 export class ClearcutLogger {
   private static instance: ClearcutLogger;
   private config?: Config;
+  private sessionData: EventValue[] = [];
+  private promptId: string = '';
 
   /**
    * Queue of pending events that need to be flushed to the server.  New events
@@ -155,6 +155,7 @@ export class ClearcutLogger {
   private constructor(config?: Config) {
     this.config = config;
     this.events = new FixedDeque<LogEventEntry[]>(Array, MAX_EVENTS);
+    this.promptId = config?.getSessionId() ?? '';
   }
 
   static getInstance(config?: Config): ClearcutLogger | undefined {
@@ -203,7 +204,10 @@ export class ClearcutLogger {
   createLogEvent(eventName: EventNames, data: EventValue[] = []): LogEvent {
     const email = getCachedGoogleAccount();
 
-    data = addDefaultFields(data);
+    if (eventName !== EventNames.START_SESSION) {
+      data.push(...this.sessionData);
+    }
+    data = this.addDefaultFields(data);
 
     const logEvent: LogEvent = {
       console_type: 'GEMINI_CLI',
@@ -319,10 +323,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_START_SESSION_MODEL,
         value: event.model,
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: this.config?.getSessionId() ?? '',
-      },
       {
         gemini_cli_key:
           EventMetadataKey.GEMINI_CLI_START_SESSION_EMBEDDING_MODEL,
@@ -379,15 +379,8 @@ export class ClearcutLogger {
           EventMetadataKey.GEMINI_CLI_START_SESSION_TELEMETRY_LOG_USER_PROMPTS_ENABLED,
         value: event.telemetry_log_user_prompts_enabled.toString(),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_VERSION,
-        value: CLI_VERSION,
-      },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_GIT_COMMIT_HASH,
-        value: GIT_COMMIT_INFO,
-      },
     ];
+    this.sessionData = data;
 
     // Flush start event immediately
     this.enqueueLogEvent(this.createLogEvent(EventNames.START_SESSION, data));
@@ -397,23 +390,12 @@ export class ClearcutLogger {
   }
 
   logNewPromptEvent(event: UserPromptEvent): void {
+    this.promptId = event.prompt_id;
     const data: EventValue[] = [
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_USER_PROMPT_LENGTH,
         value: JSON.stringify(event.prompt_length),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: this.config?.getSessionId() ?? '',
-      },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_AUTH_TYPE,
-        value: JSON.stringify(event.auth_type),
-      },
     ];
 
     this.enqueueLogEvent(this.createLogEvent(EventNames.NEW_PROMPT, data));
@@ -426,10 +408,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_TOOL_CALL_NAME,
         value: JSON.stringify(event.function_name),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_TOOL_CALL_DECISION,
         value: JSON.stringify(event.decision),
@@ -485,10 +463,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_REQUEST_MODEL,
         value: JSON.stringify(event.model),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
     ];
 
     this.enqueueLogEvent(this.createLogEvent(EventNames.API_REQUEST, data));
@@ -501,10 +475,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_RESPONSE_MODEL,
         value: JSON.stringify(event.model),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_RESPONSE_STATUS_CODE,
         value: JSON.stringify(event.status_code),
@@ -542,10 +512,6 @@ export class ClearcutLogger {
           EventMetadataKey.GEMINI_CLI_API_RESPONSE_TOOL_TOKEN_COUNT,
         value: JSON.stringify(event.tool_token_count),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_AUTH_TYPE,
-        value: JSON.stringify(event.auth_type),
-      },
     ];
 
     this.enqueueLogEvent(this.createLogEvent(EventNames.API_RESPONSE, data));
@@ -558,10 +524,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_ERROR_MODEL,
         value: JSON.stringify(event.model),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_ERROR_TYPE,
         value: JSON.stringify(event.error_type),
@@ -574,10 +536,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_API_ERROR_DURATION_MS,
         value: JSON.stringify(event.duration_ms),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_AUTH_TYPE,
-        value: JSON.stringify(event.auth_type),
-      },
     ];
 
     this.enqueueLogEvent(this.createLogEvent(EventNames.API_ERROR, data));
@@ -601,19 +559,8 @@ export class ClearcutLogger {
     );
   }
 
-  logFlashFallbackEvent(event: FlashFallbackEvent): void {
-    const data: EventValue[] = [
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_AUTH_TYPE,
-        value: JSON.stringify(event.auth_type),
-      },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: this.config?.getSessionId() ?? '',
-      },
-    ];
-
-    this.enqueueLogEvent(this.createLogEvent(EventNames.FLASH_FALLBACK, data));
+  logFlashFallbackEvent(): void {
+    this.enqueueLogEvent(this.createLogEvent(EventNames.FLASH_FALLBACK, []));
     this.flushToClearcut().catch((error) => {
       console.debug('Error flushing to Clearcut:', error);
     });
@@ -621,10 +568,6 @@ export class ClearcutLogger {
 
   logLoopDetectedEvent(event: LoopDetectedEvent): void {
     const data: EventValue[] = [
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_LOOP_DETECTED_TYPE,
         value: JSON.stringify(event.loop_type),
@@ -637,10 +580,6 @@ export class ClearcutLogger {
 
   logNextSpeakerCheck(event: NextSpeakerCheckEvent): void {
     const data: EventValue[] = [
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
-        value: JSON.stringify(event.prompt_id),
-      },
       {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_RESPONSE_FINISH_REASON,
         value: JSON.stringify(event.finish_reason),
@@ -649,10 +588,6 @@ export class ClearcutLogger {
         gemini_cli_key: EventMetadataKey.GEMINI_CLI_NEXT_SPEAKER_CHECK_RESULT,
         value: JSON.stringify(event.result),
       },
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: this.config?.getSessionId() ?? '',
-      },
     ];
 
     this.enqueueLogEvent(
@@ -732,21 +667,57 @@ export class ClearcutLogger {
     this.flushIfNeeded();
   }
 
-  logEndSessionEvent(event: EndSessionEvent): void {
-    const data: EventValue[] = [
-      {
-        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
-        value: event?.session_id?.toString() ?? '',
-      },
-    ];
-
+  logEndSessionEvent(): void {
     // Flush immediately on session end.
-    this.enqueueLogEvent(this.createLogEvent(EventNames.END_SESSION, data));
+    this.enqueueLogEvent(this.createLogEvent(EventNames.END_SESSION, []));
     this.flushToClearcut().catch((error) => {
       console.debug('Error flushing to Clearcut:', error);
     });
   }
 
+  /**
+   * Adds default fields to data, and returns a new data array.  This fields
+   * should exist on all log events.
+   */
+  addDefaultFields(data: EventValue[]): EventValue[] {
+    const totalAccounts = getLifetimeGoogleAccounts();
+    const surface = determineSurface();
+
+    const defaultLogMetadata: EventValue[] = [
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SESSION_ID,
+        value: this.config?.getSessionId() ?? '',
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_AUTH_TYPE,
+        value: JSON.stringify(
+          this.config?.getContentGeneratorConfig()?.authType,
+        ),
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_GOOGLE_ACCOUNTS_COUNT,
+        value: `${totalAccounts}`,
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_SURFACE,
+        value: surface,
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_VERSION,
+        value: CLI_VERSION,
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_GIT_COMMIT_HASH,
+        value: GIT_COMMIT_INFO,
+      },
+      {
+        gemini_cli_key: EventMetadataKey.GEMINI_CLI_PROMPT_ID,
+        value: this.promptId,
+      },
+    ];
+    return [...data, ...defaultLogMetadata];
+  }
+
   getProxyAgent() {
     const proxyUrl = this.config?.getProxy();
     if (!proxyUrl) return undefined;
@@ -760,8 +731,7 @@ export class ClearcutLogger {
   }
 
   shutdown() {
-    const event = new EndSessionEvent(this.config);
-    this.logEndSessionEvent(event);
+    this.logEndSessionEvent();
   }
 
   private requeueFailedEvents(eventsToSend: LogEventEntry[][]): void {
@@ -815,26 +785,6 @@ export class ClearcutLogger {
   }
 }
 
-/**
- * Adds default fields to data, and returns a new data array.  This fields
- * should exist on all log events.
- */
-function addDefaultFields(data: EventValue[]): EventValue[] {
-  const totalAccounts = getLifetimeGoogleAccounts();
-  const surface = determineSurface();
-  const defaultLogMetadata: EventValue[] = [
-    {
-      gemini_cli_key: EventMetadataKey.GEMINI_CLI_GOOGLE_ACCOUNTS_COUNT,
-      value: `${totalAccounts}`,
-    },
-    {
-      gemini_cli_key: EventMetadataKey.GEMINI_CLI_SURFACE,
-      value: surface,
-    },
-  ];
-  return [...data, ...defaultLogMetadata];
-}
-
 export const TEST_ONLY = {
   MAX_RETRY_EVENTS,
   MAX_EVENTS,
diff --git a/packages/core/src/telemetry/loggers.ts b/packages/core/src/telemetry/loggers.ts
index 6504c0e7..9b9faf79 100644
--- a/packages/core/src/telemetry/loggers.ts
+++ b/packages/core/src/telemetry/loggers.ts
@@ -175,7 +175,7 @@ export function logFlashFallback(
   config: Config,
   event: FlashFallbackEvent,
 ): void {
-  ClearcutLogger.getInstance(config)?.logFlashFallbackEvent(event);
+  ClearcutLogger.getInstance(config)?.logFlashFallbackEvent();
   if (!isTelemetrySdkInitialized()) return;
 
   const attributes: LogAttributes = {